Method of manufacturing refractory bottom rings

ABSTRACT

The invention provides dual wiper elements attached securely to refractory bottom rings for suspension from hot tops to be lowered into ingot molds prior to pouring hot metal thereinto, and a method of preassembling such wiper elements to said refractory bottom ring.

O Unlted States Patent 11 1 1111 3,758,942 Marcec Sept. 18, 1973 METHOD OF MANUFACTURING 3,287,872 11/1966 Focht 52 5911 REFRACTORY BOTTOM RINGS 3,352,530 1l/1967 Thiem 249/202 R26,381 4/1968 Thiem ct al.... .v 249/202 [76] Inventor: Ervm A. Marcec, 4800 Ch1 ag 3,540,689 11/1970 La Bate 249 202x Beach Dr., Chicago, 111. 60615 [22] Filed: Oct. 16, 1972 Primary Examiner-Robert D. Baldwin PP N05 297,719 Attorney-Nicholas M. Esser Related US. Application Data [63] Continuation-impart of Ser. No. 64,162, Aug. 17,

1970, abandoned.

[57] ABSTRACT [52] US. Cl. 29/475, 164/137 [51] Int. Cl B22d 7/10 The invention provides dual wiper elements attached [58] Field of Search 249/202; 29/464, securely to refractory bottom rings for suspension from 29/475; 52/597, 598; 164/137 hot tops to be lowered into ingot molds prior to pouring hot metal thereinto, and a method of preassembling [56] References Cited such wiper elements to said refractory bottom ring.

UNITED STATES PATENTS 2,258,483 10/1941 Charman 249/202 7 Claims, 7 Drawing Figures 7 21 ill (7: 1 ll l 1] W i I I k H wi l 17 22." .14

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l6 11 w ll 1 1 1 j l I r P ll l 1, ,1 l r 1;: 6 '1 I t 1 I I III: s I I I I 6 I l u? I 1 VI// PATENTED SEP 1 8 I973 sum 1 or 2 ERVIN A. M Rc c PATENTED E" 8 I915 SHEEIEUFZ Inventor Envm A. MARCEC 5 fi'l'l'orneg/ METHOD OF MANUFACTURING REFRACTORY BOTTOM RINGS This application is a continuation-in-part of application Ser. No. 64,162, filed Aug. 17, 1970, now abandoned.

This invention relates to hot tops for the pouring of metal into molds and more specifically to refractory bottom rings and wipers which are suspended from the hot top to protect the hot top casing from the molten metal being poured and to prevent metal from discharging or leaking between the hot top casing and the mouth of the mold.

Leakage of molten metal between the mold and the hot top casing can be both dangerous to personnel attending the pouring operation as well as damaging to the hot top casing. These shortcomings have been overcome by providing a dual wiper arrangement and a method for preassembling sucha wiper arrangement to an otherwise conventional refractory bottom ring at the place of manufacture, so that the assemblies can be quickly secured to the hot top casings in the metal pouring shop by means of conventional hanger clips well known in the art.

It'is accordingly the principal object of this invention to provide a new and improved refractory bottom ring for suspension from a hot top casing having a dual wiper strip' arrangement.

It is another object of this invention to preform in sections such a dual wiper arrangement for assembly to the sides of the refractory bottom ring at the place of manufacture thereof rather than in the pouring shop.

It is yet another object of this invention to provide a method for assembling and securing such a double wiper arrangement to a cured refractory bottom ring without special geometry in molding the bottom ring for retention of the wipers in place.

It is still another object to provide a novel method of forming the dual wiper elements and assembling and securing them to the outside surfaces of the refractory bottom ring.

These and additional objects and advantageous features 'will become more apparent from the following description of the invention taken in conjunction with the accompanying drawings in which:

FIG. 1 is a sectional view partially in elevation, illustrating the manner in which a refractory bottom ring provided with preassembled dual wiper strips is suspended from a hot top casing by hanger clips, and in position within the mouth of an ingot mold;

FIG. 2 is a perspective view illustrating one embodiment of the invention in which dual wiper strips have been preassembled about the refractory bottom ring;

FIG. 3 is an enlarged perspective view of a segment of the dual wiper arrangement illustrating the structure and assembly of one embodiment;

FIG. 4 is a sectional view on line 44 of FIG. 3, particularly illustrating a locating recess formed inthe side wall of refractory ring and corresponding deformation in the metal wiper assembly;

FIG. 5 is similar to FIG. 1 but illustrates a second embodiment of a dual wiper arrangement;

FIG. 6 is an enlarged perspective view of a segment of dual wiper arrangement and the structure and assembly of the embodiment illustrated in FIG. 5; and

FIG. 7 is a sectional view on line 7-7 of FIG. 6, again particularly illustrating a locating recess formed in the sidewall of the refractory ring and corresponding deformation in the metal wiper assembly.

Referring now to FIGS. l4 inclusive of the drawings, the numeral I0 designates a refractory bottom ring for suspension from a hot top in turn positioned in the mouth of an ingot mold 10b. The ring 10 is formed of such materials as refractory sands, a sodium silicate binder, and other additives for moistureproofing and the like, which is rammed in a mold box to its desired form and then fired to set the binder and to dry the refractory.

A central annulus of the refractory ring, through which hot metal is poured, is defined by a short inwardly extending lip 11, the purpose for which is to receive and support disposable refractory lining which may be inserted in the hot top casing at the pouring shop in the event the hot top casing does not have a built-in or permanent refractory lining. The outer-peripheral wall 12 of the refractory bottom ring 10 is substantially at right angles to the base 13 of the bottom ring, normal draft for the mold box being in the order of 3 to 5. The refractory bottom ring 10 may be provided in its outer walls 12 with one or more recesses 14, the purpose of which are to assist locating corresponding lugs or indentations l5 pressed from the wiper elements such as 16 and 18, so that, together with preshaped sheet metal elements confonning substantially to the configuration of the outside walls of the refractory bottom rings, all components will be in proper place for integration as by spot welding one to another around the periphery of the bottom ring as well as where they overlap one another at the corners. With proper fit up of components, recesses 14 may be found unnecessary.

In the embodiment illustrated in FIGS. 1-4, the wiper elements are of two-piece construction per outer side wall of the refractory ring. The innermost wiper element comprises a side portion 16 extending the length and depth of the outside surface or wall of the ring 10. At its upper end it is provided with an integral wiperlike lip 17 extending outwardly and upwardly at an obtuse angle to side portion 16. A second wiper element which partially overlies portion 16 is designated at 18 and is shorter in height than the underlying element 16. Element [8 is provided further with a base member 19 at substantially a right angle thereto, adapted to underlie the bottom surface 13 of the refractory bottom ring 10. The second wiper element 18 has at its upper end an integral wiper-like lip 20 extending outwardly and upwardly at an obtuse angle to its outside surface 18, spaced from and underlying the upper wiper 17. The wiper elements 16 and 18 comprise thin gauge sheet steel and are preformed or stamped so that the wiper portions 17 and 20 are sufficiently flexible to adjust to the walls of the ingot mold when lowered together with the hot top casing therein. Likewise, the sheet steel elements are preshaped or stamped to conform substantially to the configuration of the outside walls of the refractory bottom rings, which in turn are molded to confonn to the outer configuration of the hot top casing 10a. In the instance illustrated, the ring 10 is for a 34 inch hot top, the lower sides of which have a curvature of 222 inches radius. The dual wiper elements 16 and 18 have been provided with slits 21 and 22 always in alignment with one another at two or more locations on each side of the refractory bottom ring 10, to accommodate conventional hanger clips 23 as shown in FIG.

l and in phantom-line in FIG. 3, which suspend the preassembled refractory bottom ring and attached wiper strips from the hot top casing. In the embodiment illustrated, the slits are spaced 7 15 inches apart, four to a side, of a 34 inch ring. The wiper elements 16 and 18 are formed in the embodiment illustrated at their ends with a curved portion of 2 inch radius. One end of each such element is formed approximately V4 to 9% inch longer to provide for overlap with the respectively adjacent wiper elements for the other sides of the refractory ring. The overlapped portions are provided for joinder of the adjacent ends as by spot welding.

The embodiment illustrated in FIGS. 5, 6 and 7 differs from the first embodiment described above in that the wiper elements for each side of the refractory ring are made of one piece of sheet steel, as illustrated with dual wiper surfaces.

Referring to FIG. 6, the lower portion of the wiper arrangement is essentially the same as the outer elements 18, 19 and 20 of the arrangement in FIG. 3. However, at the outer end of wiper element 20, the one-piece construction of FIG. 6 continues with a reverse bend inwardly, forming surface 25, which is par allel to surface 19. Surface 25 is then bent upwardly ninety degrees to provide a surface 26 to abut flush against the outer side 12 of the refractory ring in the same plane as surface 18. Extending outwardly and upwardly at an obtuse angle from surface 18 is a wiping surface 27. As in the first embodiment, in line slits 21 are cut one above the other in the wiping surfaces .20 and 27 as well as in surface 25 for clearance of the hanger clips 23. Also, as in the first embodiment, indentations may be provided in surface 18 which cooperate with recesses 14 in the refractory wall 12 for locating the one-piece double wiper element. As noted with the first embodiment, the ends of each wiper strip are preformed for a 34 inch ring with a 2 inch radius and one end is Mi to k inch longer to overlap the adjacent wiper end for joining, as by spot welding.

The method of securing a complete set of four preformed dual wiper strips of either embodiment to an otherwise finished refractory bottom ring is as follows:

The cured refractory ring is placed in a fixture. Wiper strip elements as hereinbefore described are then located on the respective sides of the refractory ring by means of the locating indentations 15 and recesses 14, preferably with the left ends overlapping. Pressure in a direction normal to the wiper strip elements is then applied at various points against the thus loosely assembled wiper strip elements on each side of the refractory bottom ring, including the corners where the ends overlap, and preferably at a plurality of positions intermediate the corners as indicated by the arrows in FIG. 2, all

- the way around the ring. The pressure is applied preferably by fixtured pneumatically operated air cylinders and pistons to securely butt the wiper elements up to the outer surface of the ring as located by the recesses 14 and indentations 15. Thereafter, spot welding is applied, preferably by an arc spot welding gun, to are spot weld the overlapping ends together, and in the case of the first embodiment, also the overlapping elements 16 and 18 at suitable points between the air cylinders to secure surfaces 16 and 18 together as well.

When the spot welding is completed, the air cylinders are released and the completed ring is removed from the assembly fixture. It is then ready for shipment. The

construction is such that the completed rings may be stacked and strapped on pallets for shipment.

The metal wiper elements are in tight frictional engagement with the sides of the refractory bottom ring, and due to the portion of the wiper elements 19 extending below the bottom ring, as well as the locating indentations 15, the wiper elements cannot pull away as the completed bottom ring and wiper elements attached by hanger clips thereto are lowered into the mouth of the ingot mold. The wiper blade elements 20 and 21 are sufficiently flexible to conform to the walls of the mouth of the ingot mold. In the second embodiment, the wiper surfaces 20 are less flexible due to the stiffening of surface 25, but are sized to snugly enter the mouth of the ingot mold. In the event hot metal rises beyond the lower wiper 20, it will take a final chill at wiper 21, thus insuring against leakage of hot metal beyond the ingot mold.

Having described my invention in detail, it will be apparent to those skilled in the art that other embodiments will be suggested. The appended claims are intended to cover all such equivalent structures as fall within the scope thereof.

I claim:

1. Method of manufacturing a refractory bottom ring for a non-disposable hot top comprising the steps of molding and firing a refractory material to define a bottom ring having a central opening, a flat bottom, and a plurality of upstanding outside surfaces, preshaping from sheet steel a plurality of wiper bearing elements provided with wipers one above another and at least one set of which are flexible and forming indentations therein for engagement with corresponding portions of the refractory material, locating said elements along each outside surface and adjacent bottom surface, overlapping one end of each said preshaped wiper bearing element with the end of the next adjacent wiper bearing element, applying pressure normal to each of said wiper bearing elements at a plurality of locations between and including the overlapping ends to snugly position them against the upstanding outside surfaces of the refractory ring, and welding said overlapping ends of the dual wiper elements together pressed into snug engagement with the fired refractory material.

2. Method of claim 1, including providing each preshaped wiper bearing element with a flexible wiper extending angularly outwardly and overlying another wiper in spaced relationship.

3. Method of claim 1, including the steps of positioning along each outside surface and adjacent bottom surface of the refractory material, a one-piece preshaped element having formed thereon one flexible wiper extending upwardly and outwardly therefrom and one substantially inflexible wiper extending upwardly and outwardly therefrom, and in spaced arrangement from said flexible wiper.

4. Method of claim 1, including the steps of first positioning along each outside surface of the refractory material a one-piece preshaped element having formed thereon one flexible wiper extending upwardly and outwardly therefrom, thereafter positioning in overlapping fashion another one-piece preshaped element of lesser height having formed thereon one flexible wiper extending upwardly and outwardly therefrom and having also formed thereon a lip underlying the adjacent bottom surface of the refractory material, and welding the overlapped elements together.

5. Method of claim 1, in which the securing of all said overlapping elements is accomplished by arc spot weldmg.

6. Method of claim 2, in which the flexible wiper is positioned above'a substantially non-flexible wiper and the non-flexible wiper having a lip underlying the adjacent flat bottom portion of the refractory material.

7. Method of manufacturing a refractory bottom ring for a non-disposable hot top comprising the steps of molding and firing a refractory material to define a bottom ring having a central opening, a flat bottom, and a plurality of outside surfaces substantially normal to said flat bottom having a plurality of recesses therein, preshaping from sheet steel preformed elements each having a flexible wiper extending angularly outwardly from its upper end and forming a plurality of indentations in at least some of said elements for engagement with the said plurality of recesses indexing certain of said elements along each of said outside surfaces, positioning along each outside surface in overlapping fashion a second preformed element which overlies the lower portion of said first element as well as underlies at least in part the adjacent refractory bottom surface, each said second preformed element having a flexible wiper extending angularly outwardly from its upper end spaced from and underlying said first mentioned flexi ble wiper, overlapping the ends of each said preshaped wiper bearing element with the ends of the next adjacent wiper bearing elements, applying pressure substantially normal to all said wiper bearing elements at a plurality of locations including the overlapping ends to snugly position them against the outside surfaces of the refractory ring, and welding said overlapping elements together and in snug engagement with the tired refractory material. 

1. Method of manufacturing a refractory bottom ring for a nondisposable hot top comprising the steps of molding and firing a refractory material to define a bottom ring having a central opening, a flat bottom, and a plurality of upstanding outside surfaces, preshaping from sheet steel a plurality of wiper bearing elements provided with wipers one above another and at least one set of which are flexible and forming indentations therein for engagement with corresponding portions of the refractory material, locating said elements along each outside surface and adjacent bottom surface, overlapping one end of each said preshaped wiper bearing element with the end of the next adjacent wiper bearing element, applying pressure normal to each of said wiper bearing elements at a plurality of locations between and including the overlapping ends to snugly position them against the upstanding outside surfaces of the refractory ring, and welding said overlapping ends of the dual wiper elements together pressed into snug engagement with the fired refractory material.
 2. Method of claim 1, including providing each preshaped wiper bearing element with a flexible wiper extending angularly outwardly and overlying another wiper in spaced relationship.
 3. Method of claim 1, including the steps of positioning along each outside surface and adjacent bottom surface of the refractory material, a one-piece preshaped element having formed thereon one flexible wiper extending upwardly and outwardly therefrom and one substantially inflexible wiper extending upwardly and outwardly therefrom, and in spaced arrangement from said flexible wiper.
 4. Method of claim 1, including the steps of first positioning along each outside surface of the refractory material a one-piece preshaped element having formed thereon one flexible wiper extending upwardly and outwardly therefrom, thereafter positioning in overlapping fashion another one-piece preshaped element of lesser height having formed thereon one flexible wiper extending upwardly and outwardly therefrom and having also formed thereon a lip underlying the adjacent bottom surface of the refractory material, and welding the overlapped elements together.
 5. Method of claim 1, in which the securing of all said overlapping elements is accomplished by arc spot welding.
 6. Method of claim 2, in which the flexible wiper is positioned above a substantially non-flexible wiper and the non-flexible wiper having a lip underlying the adjacent flat bottom portion of the refractory material.
 7. Method of manufacturing a refractory bottom ring for a non-disposable hot top comprising the steps of molding and firing a refractory material to define a bottom ring having a central opening, a flat bottom, and a plurality of outside surfaces substantially normal to said flat bottom having a plurality of recesses therein, preshaping from sheet steel preformed elements each having a flexible wiper extending angularly outwardly from its upper end and forming a plurality of indentations in at least some of said elements for engagement with the said plurality of recesses indexing certain of said elements along each of said outside surfaces, positioning along each outside surface in overlapping fashion a second preformed element which overlies the lower portion of said first element as well as underlies at least in part the adjacent refractory bottom surface, each said second preformed element having a flexible wiper extending angularly outwardly from its upper end spaced from and underlying said first mentioned flexible wiper, overlapping the ends Of each said preshaped wiper bearing element with the ends of the next adjacent wiper bearing elements, applying pressure substantially normal to all said wiper bearing elements at a plurality of locations including the overlapping ends to snugly position them against the outside surfaces of the refractory ring, and welding said overlapping elements together and in snug engagement with the fired refractory material. 